Image:Apple mango and cross section edit1.jpg|thumb|Photo of one whole and one split mango displaying its seed, which is approximately 1/3 the size of the entire fruit
'''Recalcitrant seeds''' (subsequently known as '''unorthodox seeds''') are seed
s that do not survive drying and freezing during ex-situ conservation
and vice versa.
By and large, these seeds cannot resist the effects of drying or temperatures less than 10 °C; thus, they cannot be stored for long periods like orthodox seeds
because they can lose their viability. Plants that produce recalcitrant seeds include avocado
, Theobroma cacao|cocoa
, rubber tree
, some horticultural trees,
and several plants used in traditional medicine, such as species of ''Virola
'' and ''Pentaclethra
''. Generally speaking, most tropical pioneer species
have orthodox seeds but many climax...